Bone anchoring systems

ABSTRACT

Embodiments relate generally to tissue anchors and methods of deliveπng same to the intervertebral disc or other sites within the body. In some embodiments, the anchors provide increased pull-out resistance, stability and/or contact with tissue involving a reduced amount of penetration. In some embodiments, delivery methods are minimally invasive and can include linear, lateral, and off-angle implantation or driving of anchors along, against or within tissue surfaces. Several embodiments disclose anchors and anchoπng systems that effectively reconstruct or augment vertebral endplate surfaces.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. provisional application Nos.60/967,782, filed Sep. 7, 2007, 61/066,334, filed Feb. 20, 2008,61/066,700, filed Feb. 22, 2008, and 61/126,548, filed May 5, 2008.

BACKGROUND

1. Field of the Invention

The invention relates generally to tissue anchors, delivery methods, andassociated treatments. Anchors according to one or more embodiments canprovide superior pull-out resistance, stability and may, in someembodiments, increase contact with tissue involving a reduced amount ofpenetration. Delivery methods include linear, lateral, and off-angleimplantation or driving of anchors along, against or within tissuesurfaces.

2. Description of the Related Art

Anchors described herein can be used throughout the human body and havegeneral applicability to fastener art. Such anchors can be used to joinor anchor like or disparate materials or tissues together, maintainalignment of materials, reinforce a fracture within a material, andprovide an attachment site along or within a materials surface.Generally the art includes both staples and screws. For example, U.S.Pat. No. 7,131,973 to Hoffman discloses an anchor and delivery systemfor treating urinary incontinence. The distal portion of the deliverytool is curved and hooked such that pulling on the instruments handleeffects a retrograde delivery of the anchor. U.S. Pat. No. 5,366,479 toMcGarry et al. discloses a staple and delivery system. The staple isflat but contains a pair of inwardly curving prongs. U.S. Pat. No.5,391,170 to McGuire et al. discloses an angled screw driver forinserting bone screws in ligament tunnels as part of a ligamentreconstruction procedure. U.S. Pat. No. 5,217,462 to Asnis et al.discloses a screw and driver combination having threaded shank andsleeve that cooperate to hold and release the screw. U.S. Pat. No.5,002,550 to Li discloses a suture anchor with barbs and an installationtool that includes a curved needle for attaching a suture.

SUMMARY

As described above, tissue anchors exist in the prior art. However,there remains a need for anchors and anchoring systems that effectivelyreconstruct or augment vertebral endplate surfaces. There also exists aneed to effectively close defects between opposing endplates.

In one embodiment, a method of reconstructing or augmenting a vertebralendplate is provided. In one embodiment, the method comprises: providingat least a first anchor and a second anchors, wherein each anchorcomprises an upper neck and a lower bone engagement portion and whereinthe neck has an attachment site for coupling to an augmentationmaterial. The method further comprises identifying a vertebral endplatesurface adjacent damaged or removed tissue (or tissue that is otherwiseweak or in need of support) and driving the first and second anchorsinto and along the vertebral endplate adjacent the damaged tissue,wherein the lower bone engagement portion engages the vertebralendplate. The method further comprises coupling the attachment site ofthe first anchor to a first augmentation material and coupling theattachment site of the second anchor to a second augmentation material.The method also comprises positioning at least a portion of the firstand second augmentation material or the neck above the endplate surface,and connecting the first anchor to the second anchor and/or connectingthe first augmentation material to the second augmentation material,thereby reconstructing or augmenting the vertebral endplate.

In one embodiment, the augmentation material comprises a bone graft, anexpandable frame and/or cement, or combinations thereof. In oneembodiment, the augmentation material comprises a barrier, mesh,scaffold, band or suture, or combinations thereof. In one embodiment,the first augmentation material and the second augmentation material area single unit or opposing portions of a continuous construct. In otherembodiments, they are separate pieces. In one embodiment, the lower boneengagement portion comprises a shaft, prong, plate or keel, orcombinations thereof. In one embodiment, the anchors are driven into andalong the vertebral endplate at an angle of about 0 to about 90 degrees,preferably about 0-20 degrees. The step of interconnecting theaugmentation material comprises, in one embodiment, forming a bandaround the entire periphery of the endplate.

In another embodiment of the invention, a method of reconstructing oraugmenting a vertebral endplate using a laterally deliverablecurvilinear anchor is provided. In one embodiment, the method comprisesproviding an expandable frame comprising a distal connection site forconnecting to the anchor and delivering a bone graft between twoadjacent vertebral bodies. The method further comprises advancing theframe proximal to the graft and expanding the frame to retain the graft.The method further comprises advancing the curvilinear anchor betweenthe vertebral bodies proximate to the frame along a first axis andcoupling the frame to the anchor. The method further comprises drivingthe curvilinear anchor into an endplate of one of the vertebral bodiesin an arc such that the head of the anchor is roughly perpendicular tothe first axis and at least partially extends above the endplate,thereby reconstructing or augmenting the endplate. In severalembodiments, an interbody spacer or other device is used instead of orin addition to the bone graft. In one embodiment, the anchor isdelivered from a posterior approach across the vertebral endplate anddriven into an anterior portion of the vertebral endplate.

In yet another embodiment of the invention, a method of attaching ananchor to a vertebral body endplate is provided. In one embodiment, themethod comprises (a) providing an anchor comprising an upper attachmentsite connected to lower keel member; (b) wherein the keel comprises aleading edge connected to a lower screw coupling member; (c) driving aportion of the screw coupling member into an outer surface of thevertebral body; (d) driving a portion of the leading edge of the keelmember into the vertebral body; (e) driving a portion of the upperattachment site across the vertebral endplate; wherein steps (c), (d)and (e) are performed simultaneously. The method further comprisesdriving a screw into an outer surface of the vertebral body; andcoupling the screw with the screw coupling member. The implant maycomprise anulus and/or nucleus augmentation material, or combinationsthereof.

In one embodiment, a method of attaching an anchor to a vertebral bodyendplate further comprises forming a pilot hole in an outer surface of avertebral body, aligning the screw coupling member with the hole, anddriving the anchor into the vertebral body. In one embodiment, themethod comprises attaching an implant to the upper attachment site ofthe anchor.

In one embodiment, a method of closing a defect between opposingvertebral endplates is provided. In several embodiments, a duckbill-typedevice is used. In one embodiment, the method comprises attaching afirst gate member to a superior endplate and attaching a second gatemember to an inferior endplate. Both gates have a proximal and distalend. The proximal end of the first gate is coupled to the superiorendplate. The distal end of the first gate extends medially into anintervertebral disc space. The proximal end of the second gate iscoupled to the inferior endplate. The distal end of the second gateextends medially into the intervertebral disc space. The method furthercomprises contacting the distal ends of the first and second gates toclose a defect between opposing endplates.

In one embodiment, the first and second gates have a length greater thanthe distance spanning the opposing endplates at maximum distraction. Inone embodiment, the first and second gates comprise flexible plateshaving a curved bias about a portion of the distance between theirproximal an distal ends. In another embodiment, the first and secondgates are at least partially concave. In one embodiment, the gates aremulti faceted. In another embodiment, the distal ends of the gates forman angle between about 0 to about 180 degrees.

In one embodiment of the invention, a bone anchor for insertion into afirst surface of a bone and along an adjacent second surface of saidbone is provided. In one embodiment, the anchor comprises a neck havinga length defined by a sharpened leading edge and a trailing end. Theneck comprises an attachment site along at least a portion of itslength. The neck also comprises a bottom portion terminating in two ormore keels. A single keel may also be used in some embodiments. Thekeels are configured for pull-out resistance and stability by presentinga larger surface area below or embedded within said second surface ofthe bone relative to said neck. The keels form an angle from about 10 toabout 180 degrees relative to each other. The keels comprises sharpenedleading edges. The attachment site is offset relative to both theanchor's angle of insertion and said neck to present said attachmentsite along the second surface of said bone while said keels are insertedinto said first surface. The sharpened leading edges of said keels areadapted to be driven into the first surface of the bone whilesimultaneously advancing the attachment site across said second surface.The attachment site is configured for coupling to a tissue or aprosthetic implant for repairing said bone or adjacent tissue. Theanchor further comprises an arm extension rotatably or flexibly coupledto the neck along its length and terminates in at least one barb, hook,or angled projection, or combinations thereof. The bone anchor may beconfigured for use in the vertebral disc.

Although one anchor is provided in some embodiments, two, three, four,five, ten or more anchors are used in alternative embodiments. Theanchor delivery tools and instruments described below may be used todeliver any of the anchors described herein.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A-B show an axial and sagittal view respectively of a spinesegment and various anchor sites.

FIG. 2 shows an exploded view of one embodiment of a curvilinear anchorand delivery instrument.

FIG. 3 shows a perspective view of one embodiment of a curved twopronged staple type anchor.

FIGS. 4A-E show a sequence involving loading an anchor into a deliveryinstrument and forcing it out of the lateral opening at the distal endof the delivery instrument according to one embodiment.

FIG. 5 shows an exploded view of one embodiment of a delivery instrumentand detachable sleeve.

FIGS. 6A-G show a delivery sequence involving a vertebral endplateaccording to one embodiment.

FIG. 7 shows a prior art bone screw and intervertebral anatomy.

FIG. 8 shows an embodiment of an anchor according to one or moreembodiments.

FIG. 9 shows another embodiment of an anchor according to one or moreembodiments.

FIG. 10 shows another embodiment of an anchor according to one or moreembodiments.

FIG. 11 shows one embodiment a delivery tool.

FIG. 12 shows the delivery tool in the previous figure with an anchormounted

FIG. 13 shows an axial cross sectional view of a vertebral body andimplanted anchor.

FIGS. 14A-B show an expanded view and a frontal view of the implantedanchor in the previous figure.

FIG. 15 shows a sagittal view of the implanted anchor in the previousfigures.

FIG. 16 shows an axial cross sectional view of a vertebral body and adelivery tool inserted along an endplate in the vicinity of an anulusdefect or anulotomy.

FIG. 17 shows an axial cross sectional view of a vertebral body whereinan anulus reinforcement device has been implanted along and within theanulus and is attached to an anchor embedded within the vertebral body.

FIGS. 18A-C show various views and features of anchors according to oneor more embodiments.

FIG. 19 shows various profiles of the keel portion of one or moreanchors.

FIG. 20 shows a perspective view of another embodiment of an anchoraccording to one or more embodiments with a plate-like attachment meanssuitable for three sutures.

FIG. 21 shows a perspective view of another embodiment of an anchoraccording to one or more embodiments with an “eye” attachment means.

FIGS. 22A-B show embodiments of the anchor and delivery tool. FIG. 22Ashows a perspective view of another embodiment of an anchor according toone or more embodiments having a three legged keel portion and designedsuch that only the attachment portion remains proud on the tissuesurface. FIG. 22B shows a delivery tool for driving an anchor with amated surface and alignment pins.

FIGS. 23A-B show a perspective view of another embodiment of an anchoraccording to one or more embodiments having a flexible linkage member.

FIGS. 24A-C show a series of perspective views of one embodiment of ananchor and barrier system according to one or more embodiments.

FIGS. 25A-C show a series of perspective views of another embodiment ofan anchor and barrier system according to one or more embodiments.

FIGS. 26A-B show a side view and perspective view of an anchor with asharpened leading edge having a recessed region corresponding to thecupped cortical rim of a vertebral endplate.

FIG. 27A illustrates an embodiment of a stabilization assembly incombination with a separate anchor.

FIG. 27B illustrates an embodiment of an anchor secured to bone tissueand connected to an implant.

FIGS. 28A-28F illustrate various approaches of an implantation tool totarget tissue.

FIGS. 29A-29F illustrate a plurality of lateral views of variousembodiments of anchors and attachment positions and locations withrespect to patient tissue.

FIG. 30A illustrates a top view of one embodiment of a support member.

FIGS. 30B and 30C illustrate first and second configurations of anembodiment of a support member connected to an anchor.

FIG. 31A illustrates an embodiment of an anchor partially engaged with asupport member.

FIG. 31B illustrates the embodiment of anchor and support member of FIG.31A in a fully engaged configuration.

FIG. 31C illustrates a top view of an embodiment of a support member inan insertion configuration as maintained by a sleeve.

FIG. 31D illustrates a support configuration of the support member ofFIG. 31C.

FIG. 32 illustrates an embodiment including a plurality of anchorsconnected to respective gate numbers.

FIG. 33 illustrates an embodiment of anchors and attached gate membersin one embodiment of an implanted position.

FIGS. 34A-34C illustrate a plurality of embodiments of anchors andattached gate members and corresponding implantation locations.

FIGS. 35A and 35B illustrate two embodiments of anchors and attachedgate members and corresponding implantation configurations.

FIGS. 36A-36C illustrate embodiments of an anchor and attached gatemember and respective fixation locations with respect to an inner andouter surface of an anulus fibrosus.

FIG. 37 illustrates an embodiment of an anchor and attached gate memberhaving a plurality of interweaved fingers.

FIGS. 38A and 38B illustrate top and side schematic views respectivelyof various shapes and configurations of gate members.

FIG. 39A illustrates an embodiment of multiple anchors and attachedrespective gate members where the gate members are interweaved but notaligned with each other.

FIG. 39B illustrates an embodiment of multiple anchors and connectedrespective gate members wherein the gate members associated with arespective anchor are substantially aligned with each other.

FIG. 39C illustrates schematic top views of various configurations ofgate members including concave, multifaceted, and rounded.

FIG. 40A illustrates an embodiment of anchors and attached gate members,wherein opposing gate members are substantially mirror images of eachother and positioned in substantial alignment.

FIG. 40B illustrates an embodiment of anchors and attached gate members,wherein opposing gate members engage such that one gate member at leastpartially nests within the opposite gate member.

FIG. 41 illustrates an embodiment of anchors and attached gate memberswherein opposed gate members are connected by an embodiment of aconnector.

FIGS. 42A and 42B illustrate side and end views respectively ofembodiments of first and second anchor structures.

FIGS. 43A-43D illustrate one embodiment of an implantation sequence ofthe embodiments of first and second anchor structures of FIGS. 42A and42B.

FIG. 44A and 44B illustrates a side view of another embodiment of firstand second anchor structures.

FIGS. 45A-45C illustrate one embodiment of an implantation sequence ofthe embodiment of first and second anchor structures of FIG. 44.

FIGS. 46A and 46B illustrate perspective and side views respectively ofan embodiment of a support implant.

FIGS. 47A and 47B illustrate an anterior posterior view and lateral viewrespectively of an embodiment of a support implant provided with aplurality of markers configured to indicate a configuration of thesupport implant at an implantation location.

FIG. 48 and Detail A are a schematic side view of an embodiment of asupport implant including an anchor and a moveable support structureattached thereto.

FIG. 49 illustrates an embodiment of a delivery tool configured tofacilitate the implantation of embodiments of support implants.

FIGS. 50A-50E illustrate one embodiment of an implantation sequenceutilizing embodiments of the delivery tool of FIG. 49.

FIG. 51 illustrates an embodiment of delivery tool and attached supportimplant defining a plurality of adjacent locating surfaces configuredfor support and alignment with patient tissue.

FIGS. 52A-52E illustrate a plurality of configurations of a supportimplant deployed at various implantation locations.

FIGS. 53A-53C illustrate an embodiment of an implantation process andcooperating anchor and delivery tool.

FIGS. 54A-54C illustrate another embodiment of a delivery tool andembodiments of operation of the tool at various stages of animplantation procedure.

FIGS. 55A and 55B illustrate embodiments of an implantable supportanchor in an implanted side view and perspective view respectively.

FIGS. 56A and 56B illustrate embodiments of an implantable supportanchor in side view and end view respectively.

FIG. 56C and 56D illustrate the embodiments of an implantable supportanchor of FIGS. 55A and 55B and an embodiment of driver adapted for usetherewith.

FIGS. 57A and 57B illustrate perspective views of embodiments ofimplantable support anchor with a support structure and multiple keelmembers.

FIGS. 57C and 57D illustrate schematic side views of the embodimentsillustrated by FIGS. 57A and 57B in an implanted position.

FIGS. 58A and 58B illustrate perspective views of further embodiments ofimplantable support anchors.

FIGS. 59A and 59B illustrate side views of embodiments of implantablesupport anchor having a movable arm.

FIG. 59C illustrates a schematic side view of the embodimentsillustrated by FIGS. 59A and 59B in an implanted position.

FIG. 59D is a top view of the embodiments illustrated by FIGS. 59A and59B.

DETAILED DESCRIPTION

Embodiments relate generally to tissue anchors and methods of deliveringtissue anchors to the intervertebral disc or other sites within thebody. In some embodiments, the tissue anchors provide increased pull-outresistance, improved stability and/or increased contact with tissueinvolving a reduced amount of penetration. In some embodiments, deliverymethods are minimally invasive and include, but are not limited to,linear, lateral, and off-angle implantation or driving of anchors along,against or within tissue surfaces. In several preferred embodiments,bone anchors are provided.

The term “anchor” as used herein shall be given its ordinary meaning andshall also include, but not be limited to, nails, staples, screws,fasteners, sutures, spikes, tacks, keys, pegs, rivets, spikes, bolts,and pins. In several embodiments, the anchor comprises one or more tinesor prongs. In one embodiment, the anchor is forked. In some embodiments,the anchor may be straight, curved, or partially curved.

In several embodiments, the anchors disclosed herein are particularlysuited for hard tissues such as bone. In other embodiments, soft tissueanchors are provided. One or more embodiments of the anchor can bedelivered into a tissue and be secured within said tissue and resistextraction, migration, and/or rotation. Such stability is especiallyimportant in environments like the spine, where the anchor is adjacentdelicate nerve tissue such as the spinal cord. However, in severalembodiments, the anchoring system may be used in other delicatevasculature such as the aorta.

Although several examples of sites appropriate for anchors are describedherein for use in the boney tissue of the spine and particularly thevertebral endplates, anchors according to the embodiments describedherein have broad applications. For example, the anchors describedherein may be used in the radial head, ulnar head, humeral head, tibialplateau, scapula, acromion, talus, malleolus, tendons and ligaments suchas the talo-fibular ligament, anterior cruciate ligament, patella tibialtendon, Achilles tendon, rotator cuff, and other tissues such as themeniscus. Further, anchors according to one or more embodiments can bedisposed within artificial tissues and/or prosthetics.

FIG. 1A provides a sagittal view of a spine segment. Also shown arenumerous potential anchor sites and are marked as “X.” FIG. 1B is anaxial view of the same spine segment and shows other possible anchoringsites including along or within a vertebral body, endplate, transverseprocess, spinous process, facet, and pedicle. In other embodiments, ananchor can be placed along the cortical rim of the endplate or mediallywithin the cancellous bone or relative to or within a pedicle, skull, orsacrum. Other anchoring sites include, but are not limited to: relativeto a defect within the disc either in the area of the defect, at theinterface of the anulus and nucleus or in the area of the nucleus.

In several embodiments, one or more anchors are used in connection withan anulus or nucleus augmentative device, as described in U.S. Pat. Nos.6,425,919; 6,482,235; 6,508,839; and 6,821,276, all herein incorporatedby reference. In one embodiment, one or more anchors are used to anchoran anulus augmentation device that is placed within or beyond a defectin the anulus to the vertebral endplates.

One or more embodiments comprise anchors or gates disclosed herein aremade at least partially of one or more of the following materials: anybiocompatible material, material of synthetic or natural origin, andmaterial of a resorbable or non-resorbable nature. The anchor may alsobe partially or wholly constructed from material including, but notlimited to, autograft, allograft or xenograft; tissue materialsincluding soft tissues, connective tissues, demineralized bone matrixand combinations thereof; resorbable materials including polylactide,polyglycolide, tyrosine derived polycarbonate, polyanhydride,polyorthoester, polyphosphazene, calcium phosphate, hydroxyapatite,bioactive glass, collagen, albumin, fibrinogen and combinations thereof;and non-resorbable materials including polyethylene, polyester,polyvinyl alcohol, polyacrylonitrile, polyamide, polytetrafluorethylene,polyparaphenylene terephthalamide, cellulose, and combinations thereof.Further examples of non-resorbable materials include carbon-reinforcedpolymer composites, shape memory alloys, titanium, titanium alloys,cobalt chrome alloys, stainless steel, and combinations thereof. In someembodiments, the anchor comprises titanium alloys or cobalt chrome.

In several embodiments, the anchor comprises an anchor body and ananchor attachment site. In one embodiment, the anchor attachment site isadapted to accept or connect to a suture, linkage element, threadedscrew, and/or provides a surface for ingrowth into an adjacentstructure. The anchor attachment site can be integral to the anchor or aseparate structure comprised of the same or different material as theanchor body. The anchor attachment site can be coupled to the anchorbody. For example, the anchor attachment site can be flexibly, rigidly,or rotationally connected to the anchor body.

The anchor attachment site can comprise one or more of the followingstructures: head, flange, plate, disc, protrusion, channel, hole, cleator eye. These structures can be placed at various positions along theanchor. For example, one or more of these structures may be placed at ornear the ends of the anchor, in the middle of the anchor, or at anyother desired position. In some embodiments, the anchor attachment sitecomprises mesh, fabric, or membrane material, or a combination thereof.The site may be parallel, perpendicular or angled with respect to thebody of the anchor. In one embodiment, the anchor attachment site islocated on an end or terminus of the anchor body.

In one embodiment, the anchor comprises one anchor body and one anchorattachment site. In another body, the anchor comprises one or moreanchor bodies and one or more anchor attachment sites. In oneembodiment, the anchor comprises one body and two attachment sites.

In one embodiment, at least a portion of the anchor or gate comprises abiologically active or therapeutic agent. For example, in someembodiments, at least a portion of the anchor can comprise growthfactors such as bone morphogenic proteins, insulin-like growth factor 1,platelet derived growth factor, and fibroblast growth factor. In oneembodiment, both the anchor body and anchor attachment portion of theanchor can be adapted to deliver a biologically active or therapeuticagent. In other embodiments, at least a portion of the anchor is coatedwith a biologically active or therapeutic agent.

Curvilinear Anchor

Anchors (including staples, nails, and other fastening or joiningdevices) according to one or more embodiments can be partially or whollyarcuate or curvilinear. The radius of curvature (the tightness orgentleness of the curve) can vary among embodiments as can the sectionof a circle corresponding to the anchor. For example, an anchor having a90 degree curve would appear as ¼ of a circle. Other ranges of curvesbetween 0-180 degrees are also possible. In some embodiments, forexample, the curvature is about 15, 30, 45, 60, 75, 90, 120, 150, or 180degrees.

An anchor can also be at least partially curved with a linear portionextending upward. In this embodiment the curved portion is adapted fordriving into a tissue and the straight portion remains proud, or abovethe surface. Depending upon how the anchor is driven into the surface,the proud portion of the anchor can be anywhere from 0-180 degreesrelative to the surface. The curvature of an embodiment of the anchorcan also be variable along the anchor. Such a variable curvature couldbe employed to increase or decrease pressure on tissues adjacent to theanchor. In one embodiment, the proud portion is about 15, 30, 45, 60,75, 90, 120, 150, or 180 degrees relative to the surface.

The surface or body of the anchor can be roughened, porous, barbed,lubricated, coated or impregnated with a biologically active ortherapeutic agent. The anchor can be in the form of a curved nail orstaple with a crown or bridge and having two or more prongs or legsextending therefrom. A slot or gap between the prongs in one ore moreembodiments of a staple can be aimed at a suture or other structurealready implanted in or along a surface and then hammered in placethereby anchoring the suture in place. The tips of the prongs of astaple can be beveled to effect a wedging action. By beveling or anglingthe inner, outer, front, and/or back of a prong tip, the prong will tendto travel in a particular direction. Moreover, the beveled tips cancomplement each other, work in opposition, or some combination thereof.In one embodiment the prong tips are beveled on the outside edge, inanother embodiment the tips are beveled on the inside edge. In yetanother embodiment, the top of one prong is beveled and the bottom ofanother is beveled. In addition, the cross section of prongs may bevariable along the length of the anchor. In one embodiment, the anchorprong's smallest cross section is at or near the tip and at its greatestfurthest from the tip, creating a wedge along the curve of the anchor.This may aid in increasing compression on all or part of the bone orother tissue in contact with the anchor.

In another embodiment, an anchor can be resiliently flexible such thatafter passing through a curved slot or deflecting surface of thedelivery device, the anchor (including staples, nails, etc) straightensout to its original shape as it is advanced out of the device and intothe tissue. The original shape, predetermined shape, first shape, orunrestrained shape can be, for example, straight, angled, corkscrew, oroffset. The prongs or legs of one or more embodiments of the anchor,such as, for example, a staple, can be straight, curved, angled,corkscrew, or offset with respect to each other.

Anchor Delivery Tool

Turning now to FIG. 2, shown is one embodiment of an anchor 3 anddelivery instrument 6 according to one or more aspects of the invention.A guide body 4 has a cylindrical grip or hand hold and first proximaland second distal end. The body 4 can be partially or fully hollow andcontain a guide way chamber 5 for holding and orienting an anchor orstaple 3 terminating in an opening at the distal end of the guide body.The opening can be oriented axially out of the front of the body orlaterally and side mounted. The guide way chamber 5 comprises a curvedor angled slot or passage and opens perpendicular or off angle (orbetween 0-180) with respect to the long axis of the guiding body. Theradius of curvature along the passage can be constant or variable alongthe sweep of the curve. A curved nail or staple 3 can be inserted withinthe chamber 5 via a side loading window. A pusher rod 1 is carriedwithin or by the body 4 and accesses or is in communication with theguide way chamber. The rod 1 has a first proximal end that can beconfigured with a head or striking surface for hammering and a seconddistal end for transmitting force to the end of a nail, staple, oranchor 3 within the guide way chamber 5. The distal end or anvil can becurved, beveled, or angled such that the linear force of the rod can betransmitted downward or along an arc as the staple 3 is driven outthrough the curved slot of the chamber 5. The rod 1 may be rigid or atleast partially flexible in construction.

Also shown in FIG. 2 is a depth stop support 2 which can be configuredas a snap on sleeve that fits over the body 4. In other embodiments adepth stop may simply be a projection off of the body that limitsfurther travel of the body and/or guide way chamber opening within oradjacent a tissue. The depth stop may also be adjustable to allow fordifferent implantation depths or locations. The depth stop may projectin one or more directions from the long axis of the tool. Depth stopsand other instrumentation described in U.S. Pat. No. 6,821,276, hereinincorporated by reference, may be incorporated in several embodiments.

FIG. 3 is an example of an embodiment of a staple or anchor 3 with twoprongs or legs that are barbed and beveled on the outside. When thestaple is driven into a surface such as a bone the prongs may or may notbend inward or be wedged together. This action will pinch and compressthe bone tissue between the prongs while pressing outwardly against thesidewalls of the bone facilitating a stable anchorage.

The series depicted in FIGS. 4A-E shows an embodiment of a deliverydevice 6 being loaded with an anchor 3 and the push rod applying forceto the anchor and partially driving it out of the curved guide waychamber opening or lateral opening. FIG. 4B also shows the depth stopsupport sleeve 2 with a vertical slot corresponding to the guiding bodydistal slot which is aligned with the midline of the anchor and can beused to precisely implant or drive the anchor or staple around a sutureor linear structure.

In FIG. 5, an embodiment of the depth stop support is shown as anattachable sleeve that fits on or over the distal end of the guidingbody. However, many of the features of the sleeve can be machined,welded or attached directly to the body if so desired. In addition tothe vertical slot corresponding to the guiding body distal slot andadjustable depth stop, an alignment projection 8 is shown. The alignmentprojection can form a right angle with the depth stop and have a beveledtip to ease insertion. The alignment tip can be a relatively flat andrectangular projection that in use can be rotated and rocked between tovertebrae or a hole in an anulus to distract the vertebrae. Upon partialor full distraction the tip and at least part of the guiding body can beinserted between the adjacent vertebral bodies. The depth stop can limitthe amount of insertion by catching the edge of one or both of theopposing vertebral endplates. Vertebral taxis or the resistance of theanulus and endplates to further distraction can serve to immobilize theguiding body as the anchor is hammered out. Alternatively the body canbe wedged along an inferior superior plane to drive the opening of theguide way chamber against the desired anchor site. In another embodimentone or more depth stop surfaces may contain one or more barbs, spikes,nails, fasteners, or means for engaging or immovably coupling the distalend of the body to a boney structure such as a vertebral body. In oneembodiment an upper depth stop surface may be configured to engage asuperior vertebral body and a lower depth stop surface may be configuredto engage an inferior vertebral body.

Although the push rod and hammering method described infra is apreferred method of delivery other methods and devices can be used forthis purpose. For example, compressed gas and hydraulics can be utilizedfor driving. The push rod can be configured as a piston or threaded rod(that can be rotated to expel the implant) for imparting linear force.Also, the threaded rod or piston can be flexible or have joints alongits length to accommodate a curved or flexible guiding body.

Delivery instruments and devices according to one or more embodimentscan also be used to implant other devices besides anchors and the like.For example, a prosthetic device (including, but not limited to, abarrier, mesh, patch, or collapsible implant) can be attached or coupledto an anchor according to several embodiments of the present invention,such as described in U.S. Pat. Nos. 6,425,919; 6,482,235; and 6,508,839;6,821,276, all herein incorporated by reference. In several embodiments,the prosthetic device can be loaded within or along the guiding body ofthe device. The anchor and the prosthetic device may be constructed fromidentical, similar, or different materials. The anchor and prostheticdevice may be coupled or removably or reversibly. Connections betweenthe anchor and the prosthetic device may be temporary (such asrestorable or dissolvable sutures) or permanent. Instead of a prostheticdevice that is coupled or attached to the anchor, the prosthetic devicemay also be of unitary construct or integral with the anchor.

In one embodiment, an implant such as collapsible patch is coupled tothe anchor and oriented along or within the guiding body such that asthe anchor is passed through the guide way chamber slot in a downwarddirection the patch is extruded outwardly or parallel to the long axisof the body. The patch can be held within the body which can have linearslot adjacent the curved slot of the guide way chamber or alternativelythe patch can be mounted around the guide way chamber while coupled tothe anchor within the chamber. Also, the depth stop sleeve can also beused to compress and hold the patch in place.

In a further embodiment, one or more anchors can be delivered separatelyfrom one or more implants. In one embodiment, the implant is firstdelivered and positioned and then anchored in place. In anotherembodiment, the anchor is first established in the implantation site andthen the implant is delivered and connected to the anchor.

FIGS. 6A-L depicts an implantation sequence according to variousembodiments. FIG. 6A is an axial cross section of a vertebral body,shown is a star shaped treatment zone along the vertebral endplate. Thesequence shows an anchor being implanted into a posterior portion of avertebral body along an endplate. The surface of the endplate can beaccessed through a hole in the anulus. The hole in the anulus may be anaturally-occurring defect or surgically created. Methods and devices ofthe various embodiments are not limited to a single location along avertebral body or surgical approach.

Perpendicularly Driven Anchor

Various embodiments of anchor presented herein are designed to improveupon the weaknesses in conventional bone screws and staples that arelimited by surgical access and suture or anchor attachment siteplacement. For example, in the environment of the spine, the posteriorelements of vertebral bodies forming facet joints, spinal canal, neuralforamen, and the delicate nerve tissues of the spinal cord createnumerous obstacles for surgery and diagnostic and interventionalmethods. Surgical approaches have been adapted to minimize damage tothese structures and involve tight windows usually off angle to thetarget tissue.

An example of such prior art anchor and environment is depicted in FIG.7, which shows a bone screw driven into a vertebral body from aposterior lateral approach. Here the anchor on the outside of thevertebral body is ineffective for retaining an implant within the discand remains in dangerous proximity to the spinal cord. Severalembodiments are particularly advantageous because the anchor does notpresent attachment sites originating at a proximal end in the axialorientation from which they are driven. Moreover, several embodimentsare advantageous because the anchor is adapted with an expansionmechanism that provides a “mushrooming” effect, and thus the pull-outresistance is not merely limited to the friction and forces generated bythe sidewalls of the material or tissue.

Several embodiments accommodate or exploit certain geometries oranatomical structures of the body. For example, in one embodiment, theattachment site of an anchor can be presented distally from theinsertion site in a direction perpendicular or offset from the axialorientation of insertion. In one embodiment, the anchor presents alarger surface area below or embedded within a surface, thereby offeringimproved pull-out resistance without requiring an expansion or“mushrooming” step or mechanism.

In several embodiments, one or more anchors are driven into the surfaceof a first plane and present a portion on an adjacent plane or surfaceperpendicular or angled relative the first plane. Thus, the anchor isdriven into a first surface and across an adjacent surface in the sameinstance. In one or more embodiments, at least a portion of the anchorsuch as the anchor attachment site is adapted to remain above or proudof the upper or second tissue surface or plane. With respect to thefirst surface (the front facing or lower surface into which the anchoris driven), the anchor can be driven in to a depth such that it iscountersunk, left flush, or left partially external to the frontaltissue surface or plane. The anchor can also be delivered at atrajectory or angle relative to the second or top surface such that itis driven into the first surface and downwardly or upwardly across thesecond surface.

In several embodiments, the anchor is a flat plate-like nail or bradhaving a specialized keel portion and neck portion. In other embodimentsthe anchor is flat, plate-like, curved, corrugated, round, or acombination thereof. The neck can be terminated in a head or present anattachment portion along its length. The attachment portion or site canbe comprised of a more flexible piece of fabric, wire, linkage, fastenercomponent, hook eye, loop, or plate. The neck can be an extension,ridge, midline, or the apex of the keel portion. The neck can beoriented at the distal or proximal end of the keel or anywhere along itslength. The neck can be the same length as, longer than, or shorter thanthe keel but preferably it is shorter. In one embodiment, the neck is athin rod or beam. The keel portion can have a cross-section similar to awedge, “V”, “U”, “T”, and “W”, “X”, “O” and other shapes.

Anchors according to one or more embodiments have dimensions suitable tothe implantation environment. For example, in one embodiment, the anchorhas a height of about 0.2 cm to about 5 cm and a width of about 0.2 cmto about 5 cm. Anchors can have a length or depth from 0.2 cm to about 5cm. In some embodiments, the length, width, height or depth can be lessthan 0.2 cm or greater than 5 cm. In one embodiment, the anchor has alength of about 1 cm and a width of about 0.5 cm. In yet anotherembodiment, the anchor has a length of about 0.5 cm and a width of about0.25 cm. In another embodiment, the anchor is dimensioned as follows:about 0.3 cm wide, 1 cm long and 0.5 cm deep.

The length of the anchor can define a straight or curved line defined bya radius of curvature of about 0-90 degrees (e.g., about 15, 30, 45, 60,or 90 degrees). The keel, legs, extensions, blades, or fins can have aleading edge that is sharpened, left dull, or serrated. Other featuresof the neck and keel or extensions include, but are not limited to,barbs, tabs, roughened surface geometry, polished surface, coatingsseeded carrier or drug eluting coatings or elements, concavities,scalloped ridges, grooves, “feet”, ridges, voids, slots, and ingrowthopenings are shown in the attached drawings. Secondary edges or ribs canprotrude along portions of the keel to provide enhanced engagement withtissue. The neck or keel(s) can be hollow or tubular to accept tissueincorporation, cement, adhesive, therapeutic agents or another implantincluding a screw or pin. Portions of the keel or neck can further beexpanded after implantation and/or portions of the neck or keel can bedeflected or deployed as barbs after the anchor is initially implanted.

In addition to the neck and anchor attachment site, the anchor can alsoinclude an alignment means, engagement means or guide. Variations of theanchor alignment means can function to orient the anchor to a driver andcouple it thereto. The anchor alignment means can comprise alignmentcomponents such as a protrusion, recess, or fastener component mated toa portion of a delivery instrument. The anchor engagement means cancomprise engagement components or portions such as spikes, teeth,prongs, barbs, friction zones, or a combination thereof. The guide cancomprise a protrusion, slot, arrow, tab, or a combination thereof. Thus,in some embodiments, the anchor comprises means to align, means toengage, means to guide, or a combination thereof.

Turning to the drawings, FIG. 8 shows an embodiment of an anchor 25 witha leading edge 12, suture attachment sites 11, ingrowth features orvoids 13, first and second plate-like legs or lateral extensions 15, 15′defining the keel, arcuate central ridge or apex 10, centering oralignment projection 16, and feet or ridges 14, 14′. Both the wedge-likeshape of the keel portion of the implant i.e., the legs and the ridgesor flange like extensions at the end of the legs function to hold theimplant within a given tissue and to resist rotation and pull out from avariety of angles. The voids and ingrowth features serve to providesecondary stabilization over time and/or to allow chemical transfer orcellular respiration across the implantation site.

In a “V” shaped anchor or similar embodiment shown, the neck portion isbifurcated into two legs, extensions, blades, fins, or keels that meetat an apex and form an angle between about 10 and about 170 degrees. Inone embodiment, the angle is about 30-90 degrees. The apex at the pointof bifurcation can define a flat ridge or vertical extension or neckthat can contain one or more anchor attachment sites. In a “U” shapedembodiment the neck can be in the form of an arc or eye projecting alongthe length of the body of the anchor. “V” or “U” shaped anchors can bemodified to “L” shaped anchors in some embodiments.

In FIG. 9, an anchor similar to the one depicted in the previous figureis shown. The apex 10, which would correspond to the neck in otherembodiments, does not extend and instead presents a smooth curve whichcan present a less injurious profile to the anatomy in certainapplications. Also shown are ridges 70 and scalloped teeth-like surfacefeatures 71.

FIG. 10 shows another embodiment of an anchor with deployed barbs 80 and80′ These features can be held compressed within a sleeve on a deliveryinstrument or simply forced to compress inwardly as the implant isdriven in to tissue. One or more slots or recesses 82 are adapted forholding the barbs during implantation to streamline the anchors profile.

One or more barbs can exert continuous outward pressure on the sidewallsof a tissue or expand to form a shelf or flange if the tissue geometrywidens, expand or become more pliant. For example, in a vertebral bodythe implant might be driven into cortical bone and then further intocancellous bone. Upon reaching the cancellous bone, the barbs flexibleplate-like structure or engagement means, can expand or extend outwards.In another example the anchor is driven at least partially into thehollow of a boney structure such that the barbs expand and engage theinner wall of the bone. Element 81 can be arranged as an opposing barbor expansion means however one or more barbs 80, 81 can be orientedrelative to each other from 0-360 degrees. For example, the barbs orother barb-like components may be orientated relative to each other atthe following angles: 15, 30, 45, 60, 90, 120, 150, 180, or 360 degrees.

FIG. 11 shows a delivery tool with a shaft 96 with distal end 95 havingan anvil or striking surface 94 defining a leading edge mated to atleast a portion of the cross section of the trailing edge of the anchor.The shaft may be connected at its proximal end to a handle or terminatein a striking surface. Because a contour and size of the anvil surfaceis similar to those of the anchor in some embodiments, both the anchorand at least part of the distal end of the delivery tool can be driveninto a bone thereby counter sinking the anchor. Alternatively, anchorsaccording to one or more aspects of the invention can be left flush orpartially countersunk. A mounting member 90 may extend beyond theimplant when the implant is mounted or loaded on the tool. The mountingmember 90 includes a flattened lower surface 93 and a rounded bluntfront surface 91 for positioning along a bone surface, such as the topof a vertebral endplate, and a slot or engagement means 92 for acceptingand aligning an anchor.

FIG. 12 shows the anchor 25 mounted on the mounting member 90. Theextended lower surface 93 and the leading edge of the implant 12 and 12′forms a means to engage bone or other tissue. In one embodiment, thetissue (e.g., bone) engagement means comprises a device having an angledsurface that may be used to hook onto, engage, or align the instrumentwith the edge of a vertebral body or the intersection of two tissueplanes. In one embodiment, the engagement means can be used to align theimplant with the top of a vertebral endplate and its front outersurface, the anchor is then driven into and across the endplate.

FIG. 13 shows a cross-section of a vertebral body 24 having an anulusfibrosus 23 bounding nucleus pulposus 22 with an anchor 25 embedded intoa posterior aspect of an endplate and within or proximal to an anulotomyor defective region of the anulus fibrosus 23. This implantation site isalso in the vicinity of the cortical rim or ring of dense bone of thevertebral endplate. The anchor is shown countersunk into the bone alongthe P-A axis but partially proud along the inferior-superior axis (thedotted lines indicating the portion of the implant below bone surface orlevel.

FIG. 14A is an expanded view of FIG. 13 and shows dotted lines torepresent the keel portion of the anchor 25 beneath the endplatesurface. FIG. 14B is a dorsal view of FIG. 14A showing anchor 25.

In FIG. 15, a sagittal view of an implanted anchor 25 is shown at leastpartially within the defect 33 and inferior vertebral body 32. Superiorvertebral body 31 is also shown. The cross-section of the vertebralbodies depicts the denser and thicker cortical bone at the edge or rimwhere the anchor is implanted and the less dense cancellous bone withinthe vertebral body.

FIG. 16 depicts a method of delivery for one embodiment of the anchorand associated delivery tool. Shown is a top cross sectional view of avertebral body 24 and a delivery instrument 96 and an anchor 25. Thedelivery instrument or driver is used to transmit the force of a hammeror other means to drive the anchor in place. The driver can comprise aslot, holder, magnet, pins, mateable surfaces, fastener or other meansat its distal end to engage or couple with the anchor. The anchor canalso be attached to the distal end of the driver and then released oncethe desired delivery depth has been attained. Other features of a driver(not shown in FIG. 16) can include a depth stop, bone engagement meanssuch as a spiked, hooked, or angled protrusion, and/or a retractablesleeve to protect adjacent anatomy as the anchor is positioned. FIG. 16also shows a flat proximal end 1602 for hammering, if needed and aknurled handle 1600.

FIG. 17 illustrates a top cross-sectional view of an anulus repairimplant 52 lying along the inner surface of the posterior anulus thatcan be coupled, attached, or sutured to an anchor 25. The connectionbetween the anchor and implant can be permanent or detachable. Theimplant 52 can be delivered and positioned prior to, at the same timeas, or subsequent to the implantation of the anchor 25. FIGS. 18A-18Cshow various features of anchors.

In FIG. 18A, the surface level of a bone such as a vertebral endplate isshown as a dotted line. A side view is depicted. Here the leading edgeof the keel or leg portion of the implant is thinner than the trailingedge. Accordingly, in other embodiments of anchors at least a portion ofthe leading edge, profile, proximal edge or side of an implant can havea thinner or tapered profile than an opposing end, distal end, ortrailing edge or profile. FIG. 18B shows a series of anchor variationsfrom a side view in which the top portion, apex, neck, or implantattachment site 170, 171, 172, 173, 174 is symmetrical, rounded, wedgeshaped, oriented at the distal or proximal end of the anchor. FIG. 18Cshows another side view along the bone surface level depicting andanchors with features discussed infra such as a serrated leading edge,voids or ingrowth holes, and a recess for engaging a delivery tool.

FIG. 19 shows various embodiments of the anchor cross-sections 180-200including several keel profiles from a front view resistant to pulloutand offering various surface areas. Some are solid shapes as in anchorprofiles 182, 184, 187, and 200 and others are hollow and have an openmidsection as in anchor profiles 183, 185, 188.

Turning to FIG. 20, a perspective view of an anchor is shown withleading edges 12, 12′, alignment means 16, suture or fastener attachment11 site, neck 10, and voids 13. In this embodiment the apex does not runthe entire length or depth of the anchor corresponding to the keel oropposing leg portions 15, 15′ of the anchor. Also, the neck is orientedtowards the proximal end of the anchor forming a cut-out along the topportion of the anchor. The neck 10 is shown perpendicular to the keel 15but can be alternatively oriented in a range from 0-180 degrees relativeto it. In one embodiment, the neck is oriented at an angle of about 15,30, 45, 60, 75, 90, 120, 150, or 180 degrees relative to the keel

In FIG. 21, a “V” shaped anchor is shown. An “eye” or loop 11 isintegral to a neck extension portion 10 that bifurcates into two legs15, 15′. Because the leading edges 12, 12′ and at least a portion of theneck 10 is sharpened, this anchor can be driven more flush to the upperor first surface of a bone such as a vertebral endplate. Here both theneck 10 and the leg portions 15, 15′ of the device function as a keel.This embodiment also shows ridges 12 and scalloped recesses 170. Anchorsaccording to other embodiments described herein may also comprise ridgesand/or scalloped recesses.

In FIG. 22A, another embodiment of an anchor is shown. Here, three legs12, 12′, and 12″ defining the keel are provided. A relatively tallerneck 10 is provided beneath a perpendicular suture attachment member 11.The neck 10 is set back distally from the leading edge of the keelportion. FIG. 22B shows the distal tip of a delivery tool. Shown areattachment pins 180, anvil or striking surface 186, depth stop 187,mounting member 185, and shaft 96 with distal end 95.

Turning to FIG. 23A, an anchor 25 is shown with an attachment site 189for a flexible bridge 818. The bridge 818 is shown in FIG. 23B and iscoupled to the neck 10 of the anchor 25 with a first and second flexibletab 193, 194 and has an attachment 11 site at the opposing end.

The series depicted in FIGS. 24A-24C shows an anulus reinforcementsystem. FIG. 24A shows an anchor similar to the ones depicted previouslywith a bifurcated keel 15, 15′, neck 10, and attachment plate 112 with afirst and second coupling member 111, 111′ or snap surface. FIG. 24B isan exploded view of a barrier, mesh, or reinforcement plate 52 adjacentan anchor 25 wherein the anchor 25 is partially inserted or mountedwithin the distal end of a delivery tool. FIG. 24C shows all threeelements connected and mounted and ready to be driven into a tissuesite.

Another embodiment of an anulus reinforcement system is shown in FIGS.25A-25C. In this embodiment, a single attachment means 111 is used thatcan function as a fulcrum or hinge site for a flexible barrier 52 membershown in FIG. 25B. Behind or distal to the attachment means 111 is asupport member 112 or plate that is an extension of the neck 10. Thisfeature, in some embodiments, inhibits the barrier 52 from foldingbackwards and may also reinforce the barrier 52. FIG. 25C shows a hoodor sleeve 120 element that can be mounted on or carried by a deliverytool or instrument as described herein. The hood 120 retains the foldedbarrier until the anchor portion is fully established within the tissuewhereupon it is retracted.

Another embodiment is shown in FIGS. 26A-26B. This embodiment shows ananchor especially adapted for use in a vertebral body and includes anupside down “V” shaped keel portion with a sharpened leading edge. Theleading edges enable the anchor to be directly driven into the bone anddo not require a pilot hole or pre-cut. and One feature of thisembodiment is the leading step in the sharpened edge which presents morecutting surface blow the surface of the bone and more forward of thedistal attachment site. Alternatively, the leading edge can havemultiple steps or be curved and rounded. This profile reduces the riskthat the leading edge might pierce or damage the endplate (which is notflat but has a “dip” or cupped portion in the middle). This featurefacilitates insertion of a longer, stronger anchor into a disc thatwould otherwise (because of a pronounced dip) be difficult to positionat the proper height and depth into the bone without damaging theendplate.

The following Example illustrates one embodiment and is not intended inany way to limit the invention. Moreover, although the following Exampledescribes an anchor used in a spinal application, the anchors describedherein can be used throughout the animal body and have generalapplicability to fastener art. Such anchors can be used to join oranchor like or disparate materials or tissues together, maintainalignment of materials, reinforce a fracture within a material, andprovide an attachment site along or within a materials surface.

The anchor illustrated in FIG. 26 is used by way of example. The anchoris in the form of an upside down “Y” defined by a neck portionterminating at one end into two plate-like rectangular legs forming akeel and terminating into an suture attachment site 11 in the form of aloop on the other end. The leading edge of the legs 12 and neck 10 aresharpened and the upper portion of the legs is recessed, profiled orformed with a relief 113. The relief profile 113 can correspond to ananatomical structure. In this embodiment the forward recess or relief112 corresponds to the concavity or cupping of an endplate. The anglebetween the keel plates is around 90 degrees. The neck 10 is about 0.1millimeter high and about 0.2 wide millimeters wide and extends about0.2 millimeters. The neck 10 and attachment site 11, an “eye” or loop inthis embodiment, are mounted at the trailing or aft potion of the keel15.

The entire structure is made of nickel titanium and is machined from barstock. To be delivered, the anchor is mounted on the distal end of adriver. The driver has a striking surface on one end and an anvil on theopposing end. The anvil has the identical cross-section as the trailingedge of the anchor and extends about 0.2 cm to allow for countersinking.The anchor is coupled to the anvil by a forked protrusion that holds theneck and a pin that fits into the eye.

In one application, the anchor is used to secure an anulus repair devicerelative to a defect in the disc. A posterior-lateral approach is usedto obtain access to the damaged disc. Part of the posterior elements onthe opposing vertebral bodies may have to be removed in order to reachthe disc. The anulus repair device is then implanted through the defectand along the inner surface of the anulus.

Next the anchor, which is mounted on the distal end of the driver, isaimed at the top edge or endplate of the inferior intervertebral body.An alignment projection forming a right angle at the tip of the drive isused to align the bottom potion of the attachment loop of the anchorwith the upper surface of the endplate and to center the anchor withinthe defect. The anchor is then driven forward into the bone with lighthammering applied to the driver. The anchor is driven roughlyperpendicular to the outer surface of the vertebral body and roughlyparallel to the endplate.

The depth of insertion is controlled by the 0.2 cm countersinking anviland the depth dimension of the anchor, in this case 0.5 cm for a totaldepth of 0.7 cm which is still shy of the border of the cortical rim andthe cupping of the endplate. Only the upper potion of the loop remainsproud of the endplate surface and the annular repair device can then beconnected to it with a suture.

Graft Containment

FIG. 27A illustrates a lateral view of a stabilizer assembly 250 securedto patient tissue via a first and second fastener 252 a and 252 b. Thestabilizer or spinal fixation assembly can comprise the embodimentsdisclosed in for example U.S. Pat. Nos. 6,562,040, 6,364,880 5,437,669and 5,262,911, all herein incorporated by reference. The first fastener252 a is, in one embodiment, attached to or engaged with a superiorvertebral body 31. The second fastener 252 b is attached to or engagedwith an inferior vertebral body 32. In this embodiment, the stabilizerassembly 250 is arranged towards the posterior of the superior andinferior vertebral bodies 31, 32. Also shown is anchor device 25 thatfunctions as an anterior buttress or graft containment device.

In FIG. 27A, an anchor 25 is implanted in an upper anterior region ofthe inferior vertebral body 32. A portion of the anchor 25 extends aboveor is proud of an upper surface of the inferior vertebral body 32. Inone embodiment, the portion of the anchor 25 extending above the surfaceof the inferior vertebral body 32 is arranged to block or secure agraft, frame, plate, and/or barrier 35. In this embodiment, the anchoris implanted in the anterior portion of the endplate. In otherembodiments, the anchor may be implanted in the posterior portion.Additionally more than one anchor or anchor type as disclosed herein maybe used in more than one location to block the implant. In oneembodiment, the graft 35 comprises a femoral allograft. A wide varietyof other grafts and devices, such as loose bone grafts and/or cages canalso be secured or blocked by the anchor 25.

FIG. 27B illustrates another embodiment where an anchor 25 is attachedto a lower posterior portion of a superior vertebral body 31. Inaddition to the curvilinear anchor depicted in the illustration, otheranchors disclosed herein and included in various figures may be used forthe same purpose. For example, plate-shaped or screw anchor may be used.In one embodiment, a portion of the anchor 25 is proud of the surface ofthe superior vertebral body 31 and is further arranged to block orsecure a nonfusion intervertebral device 52. The device 52 can comprisean artificial disc or partial nucleus replacement device or other typeof implant suitable for the needs of a particular implementation.

FIGS. 28A-28F illustrate a plurality of approaches of an implantationtool 6 having one or more alignment structures 7 configured to align andlocate an anchor or other implant. FIG. 28A illustrates one embodimentof a posterior lateral approach where an anchor or other implant can bedriven into the posterior rim of either adjacent spinal end plate orproximal tissue.

FIG. 28B illustrates an embodiment of a posterior approach betweenadjacent end plates and advance of the implantation tool 6 such that adistal end of the implantation tool 6 is advanced to an anterior aspectof the respective vertebral body. FIG. 28B illustrates that an anchor orother implant can be delivered to the vertebral end plate along itsanterior cortical rim or tissue proximal thereto. In some embodiments,multiple anchors or other implants can be delivered along similarapproaches to anchor or block native tissues and/or intervertebraldevices such as one or more grafts, fusion devices, cages, anulusaugmentations, nucleus augmentation devices, and the like.

FIG. 28C illustrates an embodiment of an anterior approach for deliveryof an anchor or other implant at an anterior delivery location. FIG. 28Dillustrates a transpsoas approach for delivery of one or more anchors orother implants at a proximal delivery location. FIG. 28E illustrates anembodiment of a transforaminal approach of an implantation tool 6 forproximal delivery of one or more anchors or other implants.

FIG. 28F illustrates multiple approaches of an implantation tool 6 fordelivery of a plurality of anchors or other implants at respectivedelivery sites. FIGS. 28A-28F illustrate some of a wide variety ofembodiments and appropriate approach vectors and delivery sites can bereadily determined by the clinician based on the particular needs of thepatient. In one embodiment a multitude of anchor devices are implantedabout at least a portion of the periphery of a vertebral endplateforming an elevated rim or artificial uncus. In another embodiment theanchors a placed apart and connected together with one more band, mesh,tube, plate, or suture.

FIGS. 29A-29F provide lateral or side views of various embodiments ofone or multiple anchors 25 arranged to block and/or provide anattachment/securing site for grafts 35 and/or implants 52. In FIGS.29A-29F, the left and right portions of each Figure correspondsgenerally to the outer rim or edges of superior and inferior vertebralbodies 31, 32. M addition to the curvilinear anchors depicted in theillustrations, other anchors disclosed herein and included in thefigures such as plate and keel type anchors may be employed andimplanted in a like manner as disclosed in FIGS. 29A-29F. Multipleanchors may be delivered about the periphery of the endplate or uncus topartially reconstruct damaged bone and/or tissue. Anchors may beconnected with one or more membranes and/or frames as described herein.

FIG. 29A illustrates a single anchor 25 implanted through a lower endplate adjacent a defect in the anulus fibrosus 23 proximal the corticalrim but extending inwardly into the inferior vertebral body 32. In thisembodiment, the anchor 25 is configured to block a nonfusionintervertebral device 52 from exiting the disc space to the left of theFigure while the remaining intact anulus is blocking the device fromextruding from the right side of the Figure.

FIG. 29B illustrates an anchor 25 blocking a fusion device or graft 35.In this embodiment, the anchor 25 is arranged to rest proximal to thegraft 35 but does not touch the graft 35.

FIG. 29C illustrates an embodiment where an anchor 25 is secured to aninferior vertebral body 32 such that the anchor 25 is barely proud thesurface of the inferior vertebral body 32. The portion of the anchor 25proud of the surface is connected to an intervertebral device 35 thatcan be either a fusion or nonfusion device as illustrated and describedinfra.

FIGS. 29D-29F illustrate a plurality of embodiments employing multipleanchors 25 where each anchor 25 can be substantially identical to otheranchors 25 or where different versions or configurations of anchors 25,25′ can be employed. FIGS. 29A-29F are simply illustrative of certainembodiments and a variety of configurations and placements can beadapted to the needs of a particular patient. Though the anchorsdepicted in FIGS. 27-30 are depicted as curvilinear anchors it should beunderstood that this is for illustrative purposes only and any anchordescribed herein may alternatively or additionally be used according tothe methods described.

In FIG. 29F, two opposing vertebral bodies 31, 32 are shown. Along theperiphery of the opposing endplates are implanted a series of anchoredimplants. Implants are used to augment (e.g., build up) or replaceweakened, damaged or missing hard or soft tissue, such as bone oranulus. In some embodiments, the anchored implants extend the uncus orcortical rim of the endplates. In certain embodiments, the anchoredimplants further comprise a membrane and optionally a frame. Theanchored implants comprise a head, neck or engagement surface to attachor engage an adjacent anchored implant or another device (e.g., abarrier, band, or graft). Multiple anchored implants can beinterconnected or stacked to form a fence, augmented or raised surface(e.g., above the endplate) to reduce or prevent the escape of extrusionof a graft or other material (artificial or natural) from the enclosedarea. In one embodiment, graft containment can be achieved effectivelyby using a series of interconnected anchored implants, thus augmentingthe uncus and reconstructing the endplate. Opposing endplates can bereconstructed in this manner. In one embodiment, both the inferior andsuperior endplates are reconstructed.

FIG. 30A illustrates a top view of an embodiment of a reconfigurablesupport member 60. The support member 60 is configured to block, providesupport or serve as a barrier to inhibit herniation of tissue ormigration of a graft or implant. In one embodiment, the support member60 comprises a plurality of generally rigid elongate members 62connected via interposed flexible connections 64. The flexibleconnections 64 are formed of a biocompatible resilient material to allowthe support member 60 to resiliently move between a first and a secondconfiguration. In some embodiments, the support member 60 canreconfigure itself automatically under resilient force provided by thesupport member 60 itself. In some embodiments, the support member 60 canbe reconfigured under tension or compression force applied to thesupport member 60. In some embodiments, the elongate members 62 andflexible connections 64 are formed of the same or similar materials. Theflexible connections 64 can comprise weakened regions of the supportmember 60 and/or regions where material comprising the support member 60is thinner and/or narrower than the material in the regions of theelongate members 62.

In some embodiments, the support member 60 comprises a connectionportion 66 configured to engage with an anchor 25 as illustrated inFIGS. 30B and 30C. In some embodiments, the connection portion 66engages with a corresponding anchor 25 via a friction fit. In someembodiments, the support member 60 can connect to a respective anchor 25via suturing, one or more fasteners, biocompatible adhesives, ultrasonicwelding, snap fit, or a variety of other methods, materials, and/orprocesses for joining separate elements. In some embodiments, thesupport member 60 and anchor 25 can be formed as an integral unit andneed not comprise separate interconnected components.

FIG. 31A illustrates a further embodiment of a support member 60 with acorresponding anchor partially engaged with a connection region 66 ofthe support member 60. FIG. 31A also illustrates that the support member60 defines a transverse dimension indicated by the designator T and alongitudinal dimension indicated by the designator L.

FIG. 31B illustrates a perspective view of the support member 60 fullyengaged with an anchor 25. As previously noted, connections between theanchor 25 and support member 60 can comprise a wide variety ofconnection means including multiple means for connecting the supportmember 60 and anchor 25. In one non-limiting example, the anchor 25 canconnect to the support member 60 via means for connecting comprisingboth a friction fit and a detent arrangement.

FIG. 31C illustrates a top view of the support member 60 in aconfiguration having a reduced transverse dimension and an elongatedlongitudinal dimension. In one embodiment, the configuration illustratedin FIG. 31C of the support member corresponds to a relaxed configurationfor a natural configuration of the support member absent applied force.The reduced transverse dimension T of the support member 60 canfacilitate advancement of the support member 60 towards a desireimplantation location.

In one embodiment, the support member 60 comprises an attachmentstructure 68 arranged at a first or leading end of the support member60. The attachment structure 68 can provide an attachment point forapplication of force to the support member 60. For example, a tensionforce can be applied to the leading end of the support member adjacentthe attachment structure 68 to draw the leading end rearward so as toreduce the longitudinal dimension and expand the transverse dimension.

In some embodiments, FIG. 31C illustrates the support member in aconfiguration having force applied. For example, in one embodiment, asleeve 120 can be arranged about the support member 60 to maintain areduced transverse dimension T. Removal of the sleeve 120 can then allowthe support member 60 to achieve a relaxed configuration having anexpanded transverse dimension T and reduced longitudinal dimension L. Inother embodiments, the configuration illustrated in FIG. 31C can bemaintained by one or more sutures or clamps applied to opposed lateralsides of the support member 60 to maintain the reduced transversedimension T. Removal or severing of such sutures or clamps can releasethe support member 60 to a relaxed state having an expanded transversedimension T and a reduced longitudinal dimension L. This configurationis illustrated schematically in FIG. 31D with the reduced longitudinaldimension L′ and the expanded transverse dimension T′.

Opposing Gates

FIG. 32 illustrates a side view of a support assembly 300 configured tosupport or retain patient tissue and/or a further implant member. In oneembodiment, the support assembly 300 comprises a first anchor 25 and anopposed second anchor 25′. A first gate member 302 is connected orattached to the first anchor 25 and a second gate member 302′ issimilarly connected or attached to the corresponding second anchor 25′.In some embodiments, the gate members 302, 302′ are formed of flexiblematerial. Polymers may be used. Nitinol may also be used. In someembodiments, the gate members 302, 302′ are formed of a resilient orelastic material. In some embodiments, the gate members 302, 302′ can beat least partially rigid and movably attached to the respective anchor25, 25′ under resilient pre-loading for biased movement in a desireddirection. Such embodiments provide the ability for opposed gate member302, 302′ to resiliently engage with each other to thereby provide anobstruction or resilient support inhibiting passage of patient tissue,fluids, and/or implanted materials from passing the support assembly300.

FIG. 33 illustrates a side view of a support assembly 300 in animplanted location. In this embodiment, a first anchor 25 is secured toa lower region of a superior vertebral body 31. A second anchor 25′ issecured to an upper surface of an inferior vertebral body 32. Opposedfirst and second gate members 302, 302′ resiliently engage with eachother and are connected or attached to the respective anchors 25, 25′.In this embodiment, the gate members 302, 302′ comprise a resilient andflexible biocompatible material. As illustrated in FIG. 33, the firstand second gate members 302, 302′ can flex to accommodate patientmovement and variable loading resulting therefrom while maintaining aseal or blocking function facilitated by the resilient flexibleengagement of the opposed gate members 302, 302′. For example, in anembodiment where the support assembly 300 is implanted to resistherniation of nucleus pulposus 22, the support assembly 300 via theresilient engagement of the opposed gate members 302, 302′ can resistsuch herniation while accommodating relative movement of opposed endplates. A further advantage to certain embodiments of the supportassembly 300 is that the moveable ability of the gate members 302, 302′inhibit passage of patient tissue, fluids and/or implanted materials yetallow the inflow of nutrients, tissue fluids and the like by providing aduckbill or reed valve configuration.

In some embodiments (including, but not limited to, FIG. 33), one ormore gate members 302 can be substantially rigid and moveably attachedto a respective anchor 25. A connection or coupling between asubstantially rigid gate member 302 and a corresponding anchor 25 cancomprise a flexible connection, a pivoting connection, and/or a hingedconnection. A connection between a gate member 302 and respective anchorcan further comprise a resilient or spring aspect such that the gatemember 302 is urged in a particular direction of movement. In someembodiments, a support assembly 300 can comprise an integral assemblyand need not comprise separate connected gate member 302 and anchor 25components.

In one embodiment, (including, but not limited to, FIG. 33), a method ofclosing a defect between opposing vertebral endplates is provided. Inseveral embodiments, a duckbill-type device is used. In one embodiment,the method comprises attaching a first gate member to a superiorendplate and attaching a second gate member to an inferior endplate.Both gates have a proximal and distal end. The proximal end of the firstgate is coupled to the superior endplate. The distal end of the firstgate extends medially into an intervertebral disc space. The proximalend of the second gate is coupled to the inferior endplate. The distalend of the second gate extends medially into the intervertebral discspace. The method further comprises contacting the distal ends of thefirst and second gates to close a defect between opposing endplates. Thedistal end may touch or may be adjacent to one another. In oneembodiment, the gates are partially or wholly positioned along anendplate beyond a defective region of the anulus. In another embodiment,the gates are partially or wholly positioned in the defect. In oneembodiment, the anchor portion is in the defect and the gates are infront of the defect. A method that uses the gate system to close orbarricade a defect in which the system is placed beyond the defect isadvantageous in one embodiment because it reduces or prevents theextrusion or expulsion of nuclear material through the defect (which maybe a weakened area vulnerable to additional damage). In one embodiment,the gates are about 2-4 mm wide, about 3-6 mm long, and about 0.5-2 mmthick.

FIGS. 34A-34C illustrate additional embodiments of a support assembly300 and various embodiments of implantation location. For example, FIG.34A illustrates a support assembly 300 with a first anchor 25 attachedgenerally at a lower anterior region of a superior vertebral body 31 anda second anchor 25′ attached at an upper anterior corner of a inferiorvertebral body 32. FIG. 34A illustrates an embodiment of the supportassembly 300 implanted in a defect located generally at an anteriorposition and opposite intact anulus tissue 23. FIG. 34B illustratesanother embodiment of support assembly 300 where the anchors 25 areconfigured generally as threaded or screw shaped structures. In thisembodiment, the anchors 25 are positioned generally at an anterior outersurface of superior and inferior vertebral bodies 31, 32 In thisembodiment, the opposed gate members 302 further extend from aninterstitial region between the vertebral bodies 31, 32 outwards towardsthe respective anterior surfaces of the vertebral bodies 31, 32 forconnection with the respective anchors 25. FIG. 34C illustrates afurther embodiment where the support assembly 300 is implanted atopposed inner surfaces of a superior and inferior vertebral body 31, 32along the endplates and within or beyond the anulus. The supportassembly 300 may arranged at an posterior, anterior, or lateral positionof the vertebral bodies 31, 32.

FIGS. 35A and 35B illustrate further embodiments of a support assembly300 and various embodiments of anchor 25 configurations. FIG. 35Aillustrates that the anchors 25 comprise a generally spiked or barbedplate profile configured to be driven into and attached to respectivevertebral bodies 31, 32. FIG. 35A further illustrates that the opposedanchors 25 are presented to the patient tissue in a generally verticalanti-parallel approach. FIG. 3513 illustrates an embodiment where theanchors 25 comprise a generally T-shaped or keel profile. FIG. 3513further illustrates an embodiment wherein the opposed anchors 25 arepresented to the respective vertebral bodies 31, 32 in a generallyparallel transverse approach.

FIGS. 36A-36C illustrate top views of embodiments of support assembly300 and respective implantation locations with respect to patienttissue, such as an anulus 23. FIG. 36A illustrates that an anchor 25 canbe implanted in a defect region 33 such that the anchor 25 is interposedbetween an inner surface 26 and an outer surface 27 of the anulus 23.FIG. 36B illustrates an embodiment where the anchor 25 is implantedsubstantially adjacent or flush with an outer surface 27 of the anulus23. FIG. 36C illustrates an embodiment where the anchor 25 is implantedsubstantially adjacent with an inner surface 26 of the anulus 23.

FIG. 37 illustrates a further embodiment of support assembly 300comprising a plurality of interleaved leaves or fingers 304. In someembodiments, the individual leaves or fingers 304 are generally alignedwith other leaves or fingers 304 and in other embodiments the multipleleaves or fingers 304 are not generally aligned with each other.

FIGS. 38A and 38B illustrate top and side views respectively of variousconfigurations of gate member 302. As illustrated, a gate member 302 candefine a generally non-square rectangular, a generally square, atriangular, a semi-circular, a circular, or an irregular profile. Insome embodiments, a gate member 302 comprises a plurality of leaves orfingers 304 arranged to extend in divergent directions so as to describea brush-like configuration. In some embodiments, a gate member 302 cancomprise a plurality of leaves or fingers 304 extending generallyparallel to each other so as to define a finger-like profile. Othershapes and profiles of gate member 302 are possible. FIG. 38Billustrates that gate members 302 can define a generally straightprofile, an upwardly curved, a downwardly curved, a serpentine orundulating curve, an upward angled bend, a downward angled bend, angledbends of approximately zero to ninety degrees, angled bends ofapproximately 90 degrees, angled bends of approximately ninety to onehundred eighty degrees, concave, convex, and/or multifaceted profiles.

FIG. 39A illustrates an embodiment of support assembly 300 comprisingopposed gate members 302, 302′ each having a plurality of interleavedleaves or fingers 304. In this embodiment, the individual leaves orfingers 304 of each gate member 302 extend along different paths as seenin side view or are not generally aligned with each other. FIG. 39Billustrates an embodiment of support assembly 300 having opposed gatemembers 302, 302′ each having a plurality of individual leaves orfingers 304. In this embodiment, the individual leaves or fingers 304 ofeach gate member 302 are generally aligned with each other as seen inside view.

FIG. 38C illustrates further embodiments of gate members 302 including aconcave multifaceted three dimensional profile, a concave generallysmooth monotonic profile, and a profile combining both generally smoothcurved portions and generally flat or flange contours.

FIGS. 40A and 40B illustrate embodiments of support assemblies 300comprising opposed gate members 302 having a concave profile. In oneembodiment as illustrated in FIG. 40A, opposed gate members 302, 302′are substantially mirror images of each other having similar shapes,sizes and contours. The opposed gate members 302, 302′ are furtheraligned so as to engage with each other to form a substantiallycontinuous occlusion or seal aspect of the support assembly 300. FIG.40B illustrates another embodiment where the opposed gate members 302,302′ are similar in shape and contour, however can have different sizes.In the embodiment illustrated in FIG. 40B, the opposed gate members 302,302′ are configured and arranged to engage with each other in a nestedconfiguration.

FIG. 41 illustrates a further embodiment of support assembly that can besimilar to any previously described embodiment of support assembly 300.In the embodiment illustrated in FIG. 41, a connector 306 is provided toclamp, connect or provide a pivotal axis between the opposed gatemembers 302. The connector 306 can be provided in alternative or incombination with a resilient or self-engaging aspect of the gate members302 to provide additional resistance to separation of the opposed gatemembers 302. The embodiment illustrated in FIG. 41 can be preferred inimplementations where the sealing or blocking function provided by thesupport assembly 300 is preferably provided in a bi-directional manner.

Threaded Keel Anchor

FIGS. 42A and 42B illustrate in side and end views respectivelyembodiments of a first anchor structure 310 and a second anchorstructure 312. The first and second anchor structures 310, 312 can besecured or connected to each other, for example via a fastener 314. Thefirst anchor structure comprises a first threaded profile 316 configuredto allow the first anchor structure 310 to threadably engage withpatient tissue in a well known manner. The first anchor structure 310further comprises a second threaded profile configured to threadablyengage with the fastener 314.

The second anchor structure 312 comprises an attachment structure 322that can be configured as an attachment point for sutures and/or forconnection to a separate implant (not illustrated). The second anchorstructure 312 also comprises a foot or keel structure 324. The foot orkeel structure 324 is configured to secure and align the second anchorstructure 312 for connection with the first anchor structure 310. Thefoot or keel portion 324 can be further configured to engage withpatient tissue to secure the second anchor structure 312 thereto.

FIGS. 43A-43D illustrate embodiments of an implantation and attachmentprocess for the first and second anchor structures 310, 312. Asillustrated in FIG. 43A, a pilot hole can be formed in patient tissue,for example comprising an anulus. As shown in FIG. 43B, the first anchorstructure 310 can be threadably inserted into the pilot hole via acombination of rotational and/or translational forces. As illustrated inFIG. 43C, the second anchor structure 312 can then be laterally driveninto the patient tissue and into engagement with the first anchorstructure 310, for example into the second threaded profile 320. FIG.43D illustrates in end view that the fastener 314 can be threadablyengaged with the second threaded profile 320 of the first anchorstructure 310 to secure and connect the second anchor structure 312 inposition.

FIGS. 44A and 44B illustrates another embodiment of a first anchorstructure 330 and a second anchor structure 332. The first anchorstructure 330 comprises a first engagement surface 334 configured andsized to engage with a cooperating second engagement surface 336 of thesecond anchor structure 332. The first anchor structure may be a screw.The second anchor structure may be a keel terminating in a collar orother such engagement surface. The second anchor structure may have avoid or hole that facilitates coupling to an implant (e.g., a barrier).

FIGS. 45A-45C illustrate embodiments of introduction processes forsecuring the first and second anchor structures 330, 332 to each otherand to patient tissue. As illustrated in FIG. 45A, an opening or pilothole 342 can be formed in patient tissue (e.g., vertebral body) 340.FIG. 45B illustrates that the second anchor structure 332 is introducedinto the desired location in the patient tissue 340 via a generallylinear translational introduction. However, it should be noted that theopening 342 need not be formed prior to introduction of the secondanchor structure 332. For example, the second anchor structure 332 canbe introduced to the patient tissue 340 before formation of the opening342. Formation of the opening 342 is optional and may be omitted. Forexample, depending on the relative size of the first anchor structure330 and the characteristics of the patient tissue 340, the first anchorstructure 330 can comprise a self-drilling aspect reducing oreliminating the need to form the opening 342. FIG. 45C illustrates afurther process wherein the first anchor structure 330 is threaded intothe patient tissue 340 and further so as to engage the first and secondengagement surfaces 334, 336. Thus, the second anchor structure 332 issecured and positioned both by its contact with the patient tissue 340and via connection with the first anchor structure 330 which is alsoengaged with the patient tissue 340.

FIGS. 46A and 46B illustrate in perspective and side views respectivelyembodiments of a support implant 350 configured for closing, blocking,reinforcing, and/or repairing defects, openings, or weakened areas in avariety of patient tissues. In some embodiments, the support implant 350is particularly adapted for use in the intervertebral disc region, suchas for reinforcing a weakened anulus and/or for closing defects. Thesupport implant can inhibit herniation of disc material or augmentationimplants outside the anulus or into defects in the anulus. Embodimentsof the support implant 350 provide these benefits while limitinginterference with spinal joint movement including flexion, extension,and lateral bending movement.

The support implant 350 comprises an anchor 25 that can be formedaccording to any of the previously described embodiments of anchor 25.In one embodiment, the anchor 25 describes a generally T-shaped profilehaving two keel portions extending generally at right angles to eachother. The anchor 25 can include solid features, roughness features,leading edges, or any other combination of features and profiles asdescribed herein.

The support implant 350 further comprises a support structure 352. Thesupport structure 352 can comprise one or more of meshes, grafts,patches, gates, membranes, stents, plugs, frames, and the like, suitablefor augmenting, fortifying, bulking, closing, blocking, occluding,and/or delivering one or more therapeutic and diagnostic agents toweakened or damaged tissues. The support structure 352 can beexpandable, can be concave or convex along one or multiple axes,oversized with respect to a defect region, correspond generally to thesize of the defect region, or be sized to cover all or a portion of aregion of intact tissue.

FIGS. 47A and 47B illustrate an anterior-posterior view and a lateralview respectively of embodiments of support implant 350. FIGS. 47A and47B are further presented as radiographic images, for example as may beobtained via radiographic imaging of the support implant 350 in animplanted location. As seen in FIGS. 47A and 47B, the support implant350 comprises a first marker 354 a and a second marker 354 b. Themarkers 354 a, 354 b can comprise iridium, platinum, platinum-iridiumalloys, or other materials configured to provide an enhanced in vivoimage, for example as may be obtained with radiographic imaging. It willbe appreciated that some embodiments of the support structure 352 cancomprise biocompatible materials which can be difficult to image in theimplantation environment. The markers 354 provide an enhanced ability toimage the support implant 350 and thereby determine the location andorientation of components of the support implant 350 that may beotherwise difficult to determine.

FIG. 48 and Detail A thereof provide a schematic side view illustrationof embodiments of a support implant 350 comprising a moveable supportstructure 352. In one embodiment, the support implant 350 comprises amoveable joint 356 between the support structure 352 and an anchor 25.In some embodiments, the moveable joint 356 defines a pivotable orhinged connection between the support structure 352 and the anchor 25.In one embodiment, the support implant 350 further defines first andsecond stop structures 360 a and 360 b configured to limit the range ofmotion of the support structure 352. In some embodiments, the supportstructure 352 is resiliently biased for movement in a desired direction.

FIG. 49 illustrates an embodiment of a delivery tool 370 configured tohold and deliver embodiments of support implants 350. Structure andoperation of the delivery tool 370 will be described in greater detailwith respect to FIGS. 50A-50E and 51 which illustrate a deploymentsequence employing the support implant 350 and delivery tool 370.

As shown in FIG. 50A, a distal end of the delivery tool 370 comprisesfirst guide structure 372. The first guide structure 372 is configuredto engage with corresponding guide structures 362 of the support implant350. The first guide structure 372 can be configured as one or more ofpins, posts, slots, grooves, dovetails, or other structures configuredto maintain an alignment and orientation between the delivery tool 370and the support implant 350. In some embodiments, the first guidestructure 372 engages with guide structures 362 formed in the anchor 25.

The delivery tool 370 further comprises second guide structures 374. Thesecond guide structures 374 are configured to engage with the supportstructure 352 and maintain the support structure 352 at a desiredorientation and position with respect to the anchor 25. For example,FIG. 50B illustrates the support implant 350 engaged with both the firstand second guide structures 372 and 374.

FIGS. 50C, 50D, and 50E illustrate a progression of the support implant350 engaging with the delivery tool 370. An end plate guide of thedelivery tool 370 advances towards the support implant 350 and urges thesecond guide structures 374 to induce the support structure 352 intoadjacency with the anchor 25. The adjacency of the support structure 352to the anchor 25 provides a reduced cross-sectional profile, for exampleas illustrated in FIG. 50E, to facilitate introduction of the supportimplant 350 to the desired implant location.

FIG. 51 illustrates the support implant 350 and engaged delivery tool370 at an implant location. In this embodiment, the implant locationcomprises a corner of patient tissue 340, such as a vertebral body 31,32. The support implant 350 and delivery tool 370 define in oneembodiment a pair of adjacent first and second locating surfaces 380,382. The first and second locating surfaces 380, 382 can be positionedto contact the patient tissue 340 to inhibit further movement of thesupport implant 350 or delivery tool 370 in multiple dimensions.

As illustrated in FIGS. 52A and 52B, force can be applied, for exampleat a driving surface 384 of the delivery tool 370 to urge the anchor 25into anchoring tissue. The delivery tool 370 can then be withdrawnthereby releasing engagement between the first guide structure 372 andthe anchor and the second guide structure 374 and the support structure352. The support structure 352 is then released to expand or move into adesired deployed location.

FIGS. 52C-52E illustrate a variety of embodiments of deploymentpositions for the support implant 350. FIG. 52C illustrates that theanchor 25 is driven to extend substantially within cortical bone 40 butalso to extend along an interface between the cortical bone 40 andadjacent cancellous bone 41. FIG. 52C further illustrates that themoveable support structure 352 extends to obstruct or occlude a defect33 in the anulus 23. Movement of the moveable support structure 352 canbe inhibited by one or more stop structures 360 as previously describedand/or via interference with adjacent patient tissue, for example asuperior vertebral body 31. Support structure 352 can extend proximallyfrom the anchor 25 at roughly perpendicular to the endplate in which theanchor 25 is implanted and then extend distally at an angle roughlyparallel to the opposing endplate.

FIG. 52D illustrates an embodiment where the anchor 25 is driven intoposition to anchor in both cortical bone 40 and cancellous bone 41. FIG.52E illustrates an embodiment where the anchor 25 is driven to securesubstantially solely to cortical bone 40 with little to no contact withcancellous bone 41. FIG. 52E further illustrates the anchor 25 deployedat a more medial location as compared to the more posterior locations ofanchor 25 illustrated in FIGS. 52C and 52D.

With reference to the curvilinear anchors and delivery devices depictedinter alia in FIGS. 2-4, FIGS. 53A-53C illustrate an embodiment of adelivery tool 400 adapted to drive one or more anchors into a desiredimplantation or anchor location in patient tissue (patient tissue notillustrated). FIGS. 53A-53C also illustrate embodiments of a deploymentsequence employing the delivery tool 400 and anchor 25.

As illustrated in FIG. 53A, the delivery tool 400 comprises an urgingmember 402. The urging member 402 is configured to apply a translationalforce to the anchor 25. The urging member 402 can provide force to theanchor 25 arising from impact force, hydraulic pressure, pneumaticpressure, electromagnetic force, threaded motion, and the like.

The urging member 402 defines an engagement profile 404 at a distal ordriving end of the urging member 402. The engagement profile 404 cancomprise one or more beveled or curved profiles configured to engagewith cooperating engagement profile 28 of the anchor 25.

FIG. 53 illustrates an initial or first contact position between theurging member 402 and the anchor 25 and respective engagement profiles404, 28. As illustrated in FIG. 53A, the anchor 25 initially translatessubstantially along a longitudinal axis L upon initial contact withpatient tissue. However, contact between the beveled or curvedengagement profiles 404, 28 and curvature of the anchor 25 result in acamming action inducing the anchor 25 to rotate or curve towards atransverse axis T during the progressive introduction of the anchor 25into patient tissue. In the views provided in FIGS. 53A-53C, the anchor25 rotates by approximately ninety degrees in a clockwise direction. Asshown in FIG. 53C, during final stages of introduction of the anchor 25into patient tissue, the anchor 25 expands substantially along thetransverse axis T with significantly reduced relative motion along thelongitudinal axis L of movement of the urging member 402.

FIGS. 53A-53C further illustrate a progressive camming or slidingmovement between the opposed engagement profiles 404 and 28. Theparticular profiles or contours illustrated in FIGS. 53A-53C are simplyillustrative of one example and a variety of curves and profiles can beprovided in various embodiments of the delivery tool 400 and anchor 25depending on the needs of a particular application and thecharacteristics of the target patient tissue.

FIGS. 54A-54C illustrate another embodiment of a delivery tool 500 andsequence of operation of the delivery tool 500 in advancing an anchor 25into a desired location in target tissue 522. The delivery tool 500comprises a guide body 502. The guide body 502 is configured to providea user a grasping surface for manipulating and holding the delivery tool500. The delivery tool 500 further comprises an urging member 504 totransmit force from the delivery tool 500 to one or more anchors 25.

The delivery tool 500 further comprises a drive member 506. The drivemember 506 is attached via a hinged connection 510 to the guide body502. The hinged connection 510 can comprise one or more of a pivot, pin,axle, hinge, bearings, bushings, and the like. The hinged connection 510provides pivoting or hinged movement between the drive member 506 andthe guide body 502.

The delivery tool 500 further comprises a first cam surface 512 arrangedgenerally at a forward surface of the drive member 506. The first camsurface 512 engages with a cooperating second cam surface 514 providedat a proximal end of the urging member 504. The first and second camsurfaces 512, 514 cooperate such that hinged or pivoting movement of thedrive member 506 induces a sliding relative motion between the first andsecond cam surfaces 512, 514 to urge or advance the urging member 504outwards. In various embodiments, one or both of the first and secondcam surfaces 512, 514 can include substantially flat surfaces and curvedsurfaces. The curved surfaces can describe varying radii of curvaturealong different portions of the first and/or second cam surfaces 512,514.

The delivery tool 500 also comprises a depth stop 520 that in someembodiments is adjustable in position or location. As illustrated inFIG. 54B, the depth stop 520 provides a blocking or locating functionwith respect to the target tissue 522 inhibiting undesired relativemotion between the delivery tool 500 and the target tissue 522.

FIG. 54B further illustrates a generally transversely oriented forceapplied to the drive member 506 indicated by the designator F₁ and arrowdirected generally inwardly towards the delivery tool 500 along asubstantially transverse axis T where the delivery tool 500 extendssubstantially along a longitudinal axis L. In use, a user would hold thedelivery tool 500 in a desired position, for example by grasping theguide body 502. As the user holds the delivery tool 500 in the desiredlocation, the generally transversely directed force F₁ applied to thedrive member 506 is coupled to the distal end of the delivery tool 500to a second generally transverse force F₂ directed towards the targettissue 522. In this embodiment, the delivery tool 500 acts as a thirdclass lever to transmit force applied to the drive member F₁ as asimilarly directed force F₂ at the distal end of the delivery tool 500.

As previously noted, in some embodiments, for example as illustrated anddescribed with respect to FIGS. 53A-53C, an anchor 25 can curve orrotate during an introduction procedure to transition from a generallylongitudinal approach through a transition into a substantiallytransverse approach. As the anchor 25 begins and continues transversemotion into the target tissue 522, a reaction or recoil force F₃ isgenerated tending to drive the distal end of the delivery tool 500 andthe attached anchor 25 away from the target tissue 522. As the force F₂at the distal end of the delivery tool 500 is opposite to the reactionor recoil force F₃, these forces will tend to counteract each otherhelping to maintain the distal end of the delivery tool 500 at thedesired location and facilitating more accurate and easier introductionof the anchor 25 into the target tissue 522.

As previously noted, engagement profiles 404 and 28 can be provided onthe distal end of the urging member 504 and the anchor 25 respectivelyto facilitate the transition of advancement of the anchor 25 fromgenerally longitudinal motion transitioning to generally transversemotion. The contour and relative position of the engagement profiles 404and 28 can be adapted for more efficient transmission of forceparticularly through the transition from generally longitudinal togenerally transverse movement while maintaining the delivery tool 500 insubstantially the same position and orientation.

FIG. 54C illustrates an embodiment of the delivery tool 500 and engagedanchor 25 at a generally terminal step in an advancement procedure ofthe anchor 25. It can be seen that the anchor 25 in this embodimentextends substantially in a transverse direction. FIG. 54C illustratesfurther advantages of the delivery tool 500 in providing a self-limitingfunction. The engagement between the drive member 506 and the guide body502 via the hinged connection can be configured such that motion of thedrive member 506 is limited with respect to the guide body 502. Thedimensions and contours of the urging member 504 and drive member 506and the first and second cam surfaces 512 and 514 can preferably beselected such that the inward movement limit of the drive member 506corresponds to a desired limit of advancement of the anchor 25 withrespect to the distal end of the delivery tool 500. This provides theadvantage of automatically limiting the extent of protrusion of theurging member 504 and can provide more repeatable advancement of theanchor 25 to a desired implantation depth and along a desiredintroduction path.

FIG. 55A illustrates an embodiment of anchor 600 comprising a neck/keelportion 610 and a screw portion 620 that is implanted along the axis ofan anulotomy and disc access, just below or above the disc space into anadjacent vertebral body. The neck/keel portion 610 can be independentlyrotatable so as to extend from the screw portion 620 toward the discspace, providing an anchoring platform and site 611 from which to attachsutures, graft containment devices, and/or other medical devices. Thescrew portion 620 has an outer or major diameter that includes thethreads. The base of the threads defines an inner diameter or minordiameter that forms an axle or rod to support the threads. In FIG. 55Bthe anchor 600 is illustrated including the distal tip 613 of the screwportion 620 which can be drill-tipped (for self drilling anchors), orblunt or cone shaped for anchors that are pre-drilled in a previous stepin the procedure.

In various embodiments one or more lateral projections in the form ofneck, keel, fin, or plate can be mounted along the length of a screw orproximal to either end thereof. The attachment of the keel 610 to thescrew portion 620 may provide for substantially free and independentrotation of the screw portion 620 without imparting a significantrotational force upon the keel 610. Alternatively the keel 610 can beconnected or attached to the screw portion 620 such that it is inhibitedfrom rotation before and/or after the screw portion 620 has beenimplanted.

In one or more of the embodiments the keel 610 can be aligned in adesired direction such as vertically, e.g. extending away from thevertebral endplate and into the disc space. The keel 610 can be attachedto the screw portion 620 in a number of ways. FIGS. 56A-C illustratevarious views of a screw and keel anchor assembly 600. In FIG. 56A, thekeel 610 forms a ring 630 at two locations, both with outer diametersequal to or less than the screw's minor diameter, and generallyencircling the screw's axle at a region where there are no threads and areduced axle diameter. The screw portion 620 “captures” the keel's 610ring 630 or rings and allows the screw to spin freely about the keel610.

The most proximal end of the proximal ring 630′ of the keel 610 asillustrated in FIG. 56B may also include one or more features 640 thatallow a driver to restrain rotation and align the keel 620 in thedesired direction. In the illustration this is a series of small holesin the keel ring 630 and small pins in a corresponding driver 641 (FIG.56C). FIG. 56C illustrates the anchor 600 and one embodiment of driver641 (FIG. 56D). The driver 641 also may have a shoulder (notillustrated) that rests on the bone when the bone anchor is fullyadvanced that inhibits advancing the screw 620 beyond a desired depth.

In certain other embodiments, there may be more than one neck, keel,fin, plate, or projection, joined together or independently to thescrew, in one or more directions. The keel may be bifurcated, form aring or loop and/or comprise a neck and a bridge attachment site. FIG.57A illustrates an embodiment of the anchor device 600 in which there isneck portion defining an attachment site 611 and a bifurcated keel 610and 610′. In this embodiment the keels and neck portion are mounted atthe distal tip 613 of the screw. The screw portion 620 can be concentricor offset off axis about which the one or more keels extend. FIG. 57B issubstantially similar to the embodiment illustrated in FIG. 57A exceptthat the attachment site 611 and keels 610, 610′ are mounted at theproximal end of the screw portion 620 of the anchor 600.

FIG. 57C illustrates embodiments of implants similar to the implantillustrated in FIG. 57A in an implanted orientation within anintervertebral disc. In this case the implant was delivered from ananterior surgical approach and the keel 610 and attachment site 611 ofthe implant are situated at the posterior lateral portion of theendplate. Turning to FIG. 57D, an implant similar to the implantillustrated in FIG. 57B is provided and has been delivered via aposterior lateral surgical approach.

Further embodiments can include the addition of features to control thealignment and depth of an anchor, in relation to the surgical access anddesired final implantation location of either the keel, the screw, orboth. Besides the use of stops for depth control, an indicator and/orthe use of X-ray imaging to visualize screw depth, an alignment pinoriented along the end of the keel parallel to the axis of the screw canfacilitate visual or physical alignment of the screw and keel toward thedesired location. Various lengths of screws and length and depth ofkeels, relative to the countersunk bony surface, can provide a range ofoptions in terms of patient anatomy to properly place the strongest andmost convenient anchor and neck keel platform.

In other embodiments, the keel itself need not extend perpendicular fromthe screw's longitudinal axis, but can be jogged to one or more sides ofthe screw, and/or angled toward or away from the distal end of the screwas needed to accommodate target anatomy. In some embodiments, the keelor lateral projection can be mounted or coupled at or along a medialportion of the screw, at a distal end, at a proximal end, or anywhereelse along its length.

Various embodiments of keel/screw anchor device described herein canalso be adapted to resist back-out or unscrewing or other undesiredmovement after implantation by the addition of a locking or engagingfeature. For example, once implanted to a desired depth with the bone,the keel, fin, plate, and/or projection locks or engages the screw. Inthis position the screw is inhibited from rotating because the torqueand/or translation force acting on the keel is resisted by the shearforce of the bone.

Delivery methods described herein may alternatively or in additioninclude the delivery of bone cement or any suitable adhesive within,though, or adjacent the implant. The step of delivering bone cement suchas polymethylmetacrylate (PMM) can also be used to fill in the area leftby a countersunk anchor to aid to prevent further fracture, back-out ofthe screw or keel and to aid in healing if the cement is admixed withprophylactic antibiotics other agents.

In some embodiments, anchors can be driven at trajectories other thanparallel to an endplate ranging from 1-360 and preferably 10-80 degrees.FIG. 58A illustrates an embodiment wherein a screw and keel type anchor600 is implanted in an inferior endplate at about 45 degrees relative tothe endplate. In FIG. 58B two anchors 700, 700′ with a neck and keel areimplanted in the inferior and superior endplates of a vertebral body. Inthis embodiment, the anchors 700, 700′ are implanted at angles ofapproximately 10-25 degrees.

The anchors depicted in FIGS. 58A-B (and the other anchors throughoutthe disclosure) can be implanted flush to the vertebral body or endplateor countersunk. In other embodiments, anchors are driven at or proximalto the intersection or edge of a vertebral body endplate and vertebralbody outer surface.

FIGS. 59A-D illustrate an embodiment involving a locking or back-outfeature for an anchor. FIG. 59A is a side view of an anchor having aplate-like lower keel 710 and a neck 720 extending generallyperpendicularly therefrom. The neck 720 and keel 710 can furthercomprise various features described infra. Along the neck 720 isarranged an arm or extension 725 that is rotatably or flexibly engagedto the neck and terminates in one or more barb, hook, or angledprojection 726. In other embodiments, the extension 725 is a separatefloating member that slides along the neck 720. In use, as illustratedschematically in FIG. 58B, the arm 725 is raised as the neck 720 andkeel 710 are driven across and into a bone surface. When the desiredimplantation side is reached, the arm 726 can be driven downward bystriking it along its longitudinal axis and/or released from a flexedraised position such that it rotates downward to engage and at leastpartially penetrates the bone surface, such as an endplate. The arm 725can pivot freely or be under tension to compress the bone between theplate and the arm 725. Further embodiments of this locking featureinclude arm 725 that extends beyond the plate as illustrated in FIG. 59Cand a plate 710 with voids or a “U” shaped tip 728 or engagement zone asdepicted in FIG. 59D that function to engage or couple the angledprojection 726 with the plate 710.

Any of the devices or methods herein may be used to anchor or attachimplants, grafts, tendons, patches, orthodontia, sutures, etc. in avariety of orthopedic applications including the knee, shoulder, wrist,cranium, ankle, heel and jaw.

Modifications can be made to the embodiments disclosed herein withoutdeparting from the spirit of the present invention. For example, methodsteps need not be performed in the order set forth herein. Further, oneor more elements of any given figure described herein can be used withother figures. The titles and headings used herein should not be used tolimit the scope of any embodiments. Features included under one headingmay be incorporated into embodiments disclosed under different headings.Therefore, it should be clearly understood that the forms of the presentinvention are illustrative only and are not intended to limit the scopeof the present invention. Further, no disclaimer of subject matter isintended and the scope of the embodiments disclosed herein should beascertained from a full and fair reading of the claims.

1-24. (canceled)
 25. A graft containment system, comprising: a supportmember for containing a bone graft implanted in a disc space between twovertebral bodies; and a bone anchor for insertion into an outer surfaceand an endplate of a first vertebral body, wherein the bone anchorcomprises a neck having a length defined by a sharpened leading edge anda trailing end, wherein said neck comprises an attachment site along atleast a portion of its length, wherein said support member is coupled tothe neck via the attachment site, wherein said neck comprises a bottomportion terminating in two or more keels, wherein said keels areconfigured for pull-out resistance and stability by presenting a largersurface area below the endplate and embedded in the outer surface,wherein said keels form an angle of about 10 to about 180 degreesrelative to each other; wherein each of said keels comprises sharpenedleading edges, wherein the attachment site is offset relative to boththe anchor's angle of insertion and said neck to present said attachmentsite along the first endplate, while said keels are inserted into theouter surface, wherein the sharpened leading edges of said keels areadapted to be driven into the outer surface while the support member issimultaneously advanced along and across the endplate, and wherein thesupport member is configured to block the bone graft from extruding fromthe disc space.
 26. The graft containment system of claim 25, whereinthe support member comprises a polymer and the anchor comprisestitanium.
 27. The graft containment system of claim 25, wherein the neckcomprises two keels that form an angle of about 180 degrees relative toeach other.
 28. The graft containment system of claim 25, wherein theneck comprises two keels that form an angle of about 180 degreesrelative to each other, and wherein the neck is perpendicular to saidkeels to form a “T” shape.
 29. The graft containment system of claim 25,wherein the support member comprises an anulus augmentation device. 30.The graft containment system of claim 25, wherein the support membercomprises a nucleus augmentation device.
 31. The graft containmentsystem of claim 25, wherein the support member comprises a biologicallyactive or therapeutic agent.
 32. The graft containment system of claim25, wherein the support member comprises a polymer.
 33. The graftcontainment system of claim 25, wherein the bone anchor furthercomprises an engagement portion.
 34. The graft containment system ofclaim 33, wherein said engagement portion comprises at least one barb,hook, or angled projection.
 35. The graft containment system of claim33, wherein said engagement portion comprises one or more teeth, spikesor barbs.
 36. The graft containment system of claim 33, wherein saidengagement portion comprises one or more protrusions.
 37. The graftcontainment system of claim 33, wherein said engagement portioncomprises one or more friction plates.
 38. The graft containment systemof claim 25, wherein the bone anchor comprises a biologically active ortherapeutic agent.
 39. The graft containment system of claim 25, whereinthe anchor is at least partially constructed from a material selectedfrom the group consisting of one or more of the following: nickeltitanium alloy, titanium, cobalt chrome alloy, and steel.
 40. The graftcontainment system of claim 25, wherein said support member and saidanchor are integral.
 41. A method of reconstructing or augmenting avertebral endplate to retain a graft, comprising: identifying a firstvertebral body and a second vertebral body, wherein said first vertebralbody comprises a first outer surface and a first endplate; identifying adisc space bordered by the first vertebral body and the second vertebralbody, providing a bone graft containment system comprising a bone graft,a support member for containing the bone graft, and a bone anchor,wherein the bone anchor is configured for insertion into the first outersurface and for presenting an attachment site along the first endplate,wherein the first outer surface is offset at an angle substantiallyperpendicular from the first endplate, wherein the support member iscoupled to the bone anchor; wherein the bone anchor comprises a neck,wherein said neck has a length defined by a sharpened leading edge and atrailing end, wherein said neck comprises an attachment site along atleast a portion of its length, wherein said attachment site isattachable to the support member, wherein the attachment site isconfigured to extend above the first endplate, wherein said neckcomprises a bottom portion terminating in two or more keels, whereinsaid keels are configured for pull-out resistance and stability bypresenting a larger surface area below the first endplate and embeddedin the first outer surface, wherein said keels form an angle of about 10to about 180 degrees relative to each other; wherein each of said keelscomprises sharpened leading edges, wherein the attachment site is offsetrelative to both the anchor's angle of insertion and said neck topresent said attachment site along the first endplate, while said keelsare inserted into the first outer surface; inserting the bone graft intothe disc space; driving the sharpened leading edges of the keels intothe first outer surface while simultaneously advancing the supportmember along and across the first endplate until said anchor iscountersunk within said outer surface; and positioning the supportmember to contain the bone graft, thereby reconstructing or augmentingthe endplate of the first vertebral body to minimize extrusion of thebone graft from the disc space.
 42. The method of claim 41, wherein theneck comprises two keels that form an angle of about 180 degreesrelative to each other.
 43. The method of claim 41, wherein the neckcomprises two keels that form an angle of about 180 degrees relative toeach other, and wherein the neck is perpendicular to said keels to forma “T” shape.
 44. A method of reconstructing or augmenting a vertebralendplate to retain a graft, comprising: identifying a first vertebralbody and a second vertebral body, wherein said first vertebral bodycomprises a first outer surface and a first endplate; identifying a discspace bordered by the first vertebral body and the second vertebralbody, providing a bone graft containment system comprising a supportmember for containing a bone graft and a bone anchor, wherein the boneanchor is configured for insertion into the first outer surface and forpresenting an attachment site along the first endplate, wherein thefirst outer surface is offset at an angle substantially perpendicularfrom the first endplate, wherein the support member is coupled to thebone anchor, wherein the bone anchor comprises a neck, wherein said neckhas a length defined by a sharpened leading edge and a trailing end,wherein said neck comprises an attachment site along at least a portionof its length, wherein said attachment site is attachable to the supportmember, wherein the attachment site is configured to extend above thefirst endplate, wherein said neck comprises a bottom portion terminatingin at least one keel, wherein said keel is configured for pull-outresistance and stability by presenting a larger surface area below thefirst endplate and embedded in the first outer surface, wherein saidkeel is substantially perpendicular to said neck to form a T-shape,wherein said keel comprises a sharpened leading edge, wherein theattachment site is offset relative to both the anchor's angle ofinsertion and said neck to present said attachment site along the firstendplate, while said keel is inserted into the first outer surface;inserting the bone graft into the disc space; advancing the sharpenedleading edge of the keel against the first outer surface whilesimultaneously advancing the support member along and across the firstendplate; and positioning the support member to contain the bone graft,thereby reconstructing or augmenting the endplate of the first vertebralbody to minimize extrusion of the bone graft from the disc space. 45.The method of claim 44, wherein the support member comprises a polymerand the anchor comprises titanium.